Fujitsu General AOHH30KMTB, Service Manual

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8-7. High temperature and high pressure release control
The compressor is controlled as follows.
• Cooling mode
Indoor unit heat exchanger
temperature rises Indoor unit heat exchanger
temperature drops
Stable zone
AB
BC
CD
Zone A
Zone B
Zone C
Zone D
AB: 64 °C
BC: 60 °C
CD: 58 °C
Zone Operation
Zone A Compressor is stopped.
Zone B The compressor frequency is decreased. -7 rps/120 sec.
Zone C
The protection is released and the operation is returned to normal mode.
Zone D
• Heating mode
Indoor unit heat exchanger
temperature rises Indoor unit heat exchanger
temperature drops
Stable zone
AB
BC
CD
DE
Zone A
Zone B
Zone C
Zone D
Zone E
AB: 63°C
BC: 55°C
CD: 53°C
DE: 50°C
Zone Operation
Zone A Compressor is stopped.
Zone B
The compressor frequency is decreased.
-15 rps/120 sec.
Zone C -2 rps/120 sec.
Zone D
The protection is released and the operation is returned to normal mode.
Zone E
8-7. High temperature and high pressure release control
- (04-33) -
8. Various protections
CONTROL AND FUNCTIONS CONTROL AND FUNCTIONS